The subsections below will give the details about which images you should
get for each possible means of installation.

A.2.1. CDROM

There are two different netinst CD images which can be used to install
squeeze with the debian-installer. These images are intended to boot from CD
and install additional packages over a network, hence the name 'netinst'.
The difference between the two images is that on the full netinst image
the base packages are included, whereas you have to download these from
the web if you are using the business card image. If you'd rather, you can
get a full size CD image which will not need the network to install. You
only need the first CD of the set.

Download whichever type you prefer and burn it to a CD.

A.2.2. Booting from network

It's also possible to boot debian-installer completely from the net. The
various methods to netboot depend on your architecture and netboot setup.
The files in netboot/ can be used to netboot debian-installer.

A.2.3. Booting from hard disk

It's possible to boot the installer using no removable media, but just an
existing hard disk, which can have a different OS on it. Download
hd-media/initrd.gz, hd-media/vmlinuz,
and a Debian CD image to the top-level directory of the hard disk. Make sure
that the CD image has a filename ending in .iso. Now
it's just a matter of booting linux with the initrd.